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Three des, as structural particles in Chinese, are phonologically the same, but written differently. Through analyzing the written forms of these three homophonous particles, the research has come to some valuable conclusions that cannot be obtained by only observing the speaking language of Chinese. This paper studies the relationships among three “des” (de1 as “的”; de2 as “地”; de3 as “得”), which function as structural particles in the written language of Chinese, by examining their mutual replacements in blogs. The research regards every living language as a Complex Adaptive System (CAS) with continuing changes. So this study’s perspective not only helps us understand more deeply the structures with three des, but also opens a new window to explore the variation of Chinese on the cognitive linguistic layer, including syntactic and semantic aspects. Through analyzing the authentic data, which is obtained from a corpus built of articles in personal blogs including 400,000 Chinese characters, there are several worthy findings. First, the mutual replacements are asymmetric along with the generalization of de1. Secondly, there is a positive correlation between the frequency of replacements and the linguistic positive relevance among the three des, especially the syntactic and semantic aspects. Finally, the replacements among the vii three des present a diverse and complicated situation when investigating the written forms of idiolects. The syntactic factor plays the main role in the replacements among the three des. The related degree of de1 & de2 is significantly higher than the one of de1 & de3, which is especially obvious on the writers with relatively frequent replacements.

As three-dimensional (3D) imaging and fluorescence techniques become standard in optical microscopy, novel approaches to 3D fluorescence microscopy are emerging. One such approach is based on the incoherent holography technique called optical scanning holography (OSH). The main advantage of OSH-based microscopy is that only a single two-dimensional (2D) scan is required to record 3D information, whereas most current 3D microscopes rely on sectioning techniques. To acquire a 3D representation of an object, current microscopes must physically scan the specimen in a series of 2D sections along the z-axis. In order to record holograms by OSH, the fluorescent specimen is scanned with an optically heterodyned laser field consisting of a Fresnel zone pattern. A unique acousto-optic modulator configuration is employed to generate a suitable heterodyne frequency for excitation of the fluorescent object. The optical response of a solution containing a high concentration of 15 um fluorescent latex beads to this type of excitation field has been recorded. In addition, holograms of the same beads have been recorded and reconstructed. To demonstrate the 3D imaging capability of the technique, the hologram includes beads with longitudinal separation of about 2 mm. A detailed comparison of 3D fluorescence microscopy by OSH and the confocal approach was conducted. Areas for comparison were 3D image acquisition time, resolution limits and photobleaching. The analysis shows that an optimized OSH-based fluorescence microscope can offer improved image acquisition time with equal lateral resolution, but with degraded longitudinal resolution when compared to confocal scanning optical microscopy (CSOM). For the photobleaching investigation, the parameter of concern is the fluence received by the specimen during excitation, which takes into account both the irradiance level and the time of illumination. Both peak and average fluence levels are addressed in the comparison. The analysis shows that during a 3D image acquisition, the OSH system will deliver lower peak fluence but higher average fluence levels to the specimen when compared to CSOM. / Ph. D.

Electron tomography is an invaluable technique with the capability of carrying out thorough 3D structural, chemical and morphological characterization of materials at nanometer scale. Tilting range, increment and reconstruction algorithms are three of the main factors affecting the quality of tomograms. An anisotropic degradation can be observed with restricted tilting range and increment. Therefore, this study was carried out to investigate the accuracy of the reconstruction results of MgO (cube-shape) generated by FBP, SART and SIRT tomographic algorithms under various reconstruction conditions, i.e. tilting range and increment. Examining the experimental data with known morphology permits quantitative determination of the accuracy of the reconstruction results by measuring the distortion of the cube in all directions. Moreover, distortion measurements in all directions reveal the relationship between level of distortion and the alpha tilt angle. / Master of Science

The goal of this line of research is to add to the existing body of literature on the effect of heat treatments on the microstructure of chrome-bearing white irons and add bend test data to the literature concerning chrome-bearing white irons. This project was intended to support an existing line of research into cast metal-ceramic lattices using chrome white iron as a substitute for sintered ceramic tiles used to defeat projectiles. Chrome-bearing white irons have a substantial quantity of chromium carbides, giving them high hardness and abrasion resistance. Additionally, tiles cast from white iron proved to be more durable than sintered ceramic tiles, breaking into large chunks rather than a powder following an impact. These properties make tiles cast from chrome-bearing white iron a low-cost alternative to sintered carbides. The alloy investigated contained nominally 14 chromium and 3.2 carbon by weight percent. Three-point bend test specimens were cut from cast plates. These specimens were austenitized, air cooled, then tempered prior to three-point bend and hardness testing. The microstructure of the specimens was evaluated using optical microscopy, SEM, and XRD. This line of research revealed that lower austenitization temperatures resulted in a martensitic matrix with fewer, smaller secondary carbides, resulting in higher strength and hardness. In contrast, higher austenitization temperatures produced an austenitic matrix with coarser carbides, resulting in lower strength and hardness. This research did not reveal an appreciable change in ductility over heat treatment temperature. / Master of Science / This research investigates a hard iron alloy capable of replacing expensive ceramics in situations where the goal is to prevent penetration by a projectile. This iron alloy, known as white cast iron, can be cast using typical foundry practices, making it cost-effective. Additionally, the properties can be changed by heat-treatment, a process that involves heating the material to a given temperature, holding it at that temperature for a given amount of time, then cooling the material at a given rate. The results of this research add to the existing understanding of how heat treatment affects the properties of white cast iron. Additionally, this research generated new data about the strength of white cast irons in a three-point bending test, a test not normally used for white cast irons. The research found that high heat-treatment temperatures resulted in a softer white cast iron with lower strength. The structure of the white cast iron treated at these temperatures was predominantly austenite, a soft iron phase, and large carbides, a hard but brittle phase. Temperatures close to the lower end of the temperature range tested resulted in a harder white cast iron with higher strength. The structure of the iron in these conditions contained martensite, a hard iron phase, some austenite, and smaller but more angular carbides.

Analysis of three-phase, three-level VSIs is done for high-power high-voltage applications. Complete Space Vector Modulation (SVM) algorithm is developed for a three-phase, three-level converter. Special attention is given to minimization of output ripple and voltage balance of the dc-link input capacitors. Verification of the proposed SVM algorithm is done by computer simulation. Comprehensive small-signal modeling of the three-level converter with a resistive load is developed the first time. Steady-state solutions reveal that the voltage across dc-link input capacitors is constant at the half of the dc-link voltage. / Master of Science

Current methods for treating and diagnosing spinal deformities caused by scoliosis are both surgically intensive and rarely allow for complete correction. This is mainly due to the fact that the diagnostic techniques used are rough estimates made by angles defined by observations of 2-D radiographs. By utilizing the latest software, our research is based on designing a tool that creates a 3-D representation of the spine. When creating a three-dimensional spinal model, it becomes possible to determine local curvature and local torsion values at each specific vertebrae. By manipulating these values at discrete locations on the spine, one can generate "virtual" spines in a three-dimensional environment. The Scoliosis Learning Tool includes algorithmic steps that determine the Lenke Classification of the "virtual" spines. The Lenke Classification is the most commonly accepted method for diagnosing spinal deformities. This patient building program will produce a group of spines with random values for curvature, torsion and initial spinal orientation. An algorithm within the software determines the Lenke Classification of each, and discards any curves that appear unnatural. By defining a metric that places an emphasis on certain geometric similarities, the software is able to define diameters of classification groups and separations between different classification groups. In turn it is possible to determine minor to major differences between spines within the same classification. In doing so, the opportunity exists to possibly find an undiscovered deformity that had previously fallen under another classification category. / Master of Science

A modified space vector modulation algorithm for a zero-voltage transition three-phase voltage source inverter/boost rectifier is presented. The converter is intended for high performance medium power applications requiring bi-directional power flow. The proposed modified space vector modulation allows the main switches to be operated with constant frequency and soft switching for any phase shift between the three-phase currents and voltages. The modulation algorithm also eliminates any low frequency distortion caused by the zero-voltage transition and can be extended to other soft-switching PWM three-phase converters. Experimental verification of the proposed algorithm is also presented as well as a comparison to the hard switched PWM converter. / Master of Science

There are instances where efficiency and safety may be compromised as a result of wear and tear of fluid transporting pipe systems. Consequently, it is sometimes necessary to shut down the entire operation to fix the problem. Thus, it is worth evaluating other methods that can repair the damage for a temporary period without shutting down the operation while a new pipe is being constructed. The objective was to evaluate the durability of the epoxy bonded steel in aqueous environments that might be the conditions of such a repair. EPON(registered mark)828 was chosen as the epoxy resin, and dicyandiamide and polyamidoamine were two types of curing agent evaluated in this study. The epoxy bonded steels were exposed in either distilled water or 3.4% NaCl solution for various time periods. The mechanical strengths of the bonded joints were evaluated using a three-point flexure test. The neat epoxy samples were also aged under the same conditions, and three-point flexure test and dynamic mechanical analysis (DMA) were performed to evaluate their mechanical properties. The moisture uptake of the neat epoxy increased with exposure time, and the bending modulus of the neat epoxy decreased with aging time and moisture uptake. It was found that the interfacial shear strength decreased with aging time for both epoxy bonded systems. Scanning Electron Microscopy (SEM), optical microscopy, and X-ray Photoelectron Spectroscopy (XPS) were used to determine the locus of failure of the bonded joints. It was concluded that failure occurred cohesively within the oxide layer if oxides were present on the substrate surface prior to the bonding procedure. / Master of Science

This project was born out of the work performed by a group of researchers at the New Jersey Institute of Technology (NJIT) [1] [2] [3] working on interferometric imaging with a spiral array. Their investigation stopped at two dimensional imaging with a two dimensional array. In this thesis, their idea was developed further into the significantly more complex imaging with a three dimensional array. The general design of the NJIT [1] [2] [3] experiment was reproduced, studied, and modified in a manner that was theorized to enhance the experiment with the added ability to perform three dimensional imaging. The NJIT team [1] [2] [3] has developed their experiment to where they were able to accurately perform two dimensional imaging of two sources of equal intensity located at different distances from a spiral array. In this thesis, the equations used for two dimensional imaging are extrapolated into a three dimensional array application. This three dimensional imaging concept is simulated with MATLAB and the results presented and compared to the NJIT experimental results. [1] [2] [3] A proof of concept physical experiment is conducted and the results are compared to the MATLAB simulation. The results show that additional spatial information can be obtained from a three dimensional array that can enhance the information gleaned from images. / Master of Science