In this work the transformation induced fatigue of Ni-rich NiTi shape memory alloys (SMAs) was investigated. The aerospace industry is currently considering implementing SMA actuators into new applications. However, before any new applications can be put into production they must first be certified by the FAA. Part of this certification process includes the actuator fatigue life. In this study, as-received and polished at dogbone SMA specimens underwent transformation induced fatigue testing at constant loading. The constant applied loading ranged from 100 MPa to 200 MPa. Specimens were thermally cycled through complete actuation (above Af to below Mf ) by Joule heating and environmental cooling. There were three cooling environments studied: liquid, gaseous nitrogen and vortex cooled air. It was shown that polished specimens had fatigue lives that were two to four times longer than those of as-received specimens. Test environment was also found to have an effect on fatigue life. Liquid cooling was observed to be corrosive, while the gaseous nitrogen and vortex air cooling were observed to be non-corrosive. The two non-corrosive cooling environments performed similarly with specimen fatigue lives that were twice that of specimens fatigue tested in the corrosive cooling environment. Transformation induced fatigue testing of polished specimens in a non-corrosive environment at 200 MPa had an average fatigue life of 14400 actuation cycles; at 150 MPa the average fatigue life was 20800 cycles and at 100 MPa it was 111000 cycles. For all specimens constant actuation from the beginning of testing until failure was observed, without the need for training. Finally, a microstructural study showed that the Ni3Ti precipitates in the material were one of the causes of crack initiation and propagation in the actuators.

The purpose of this qualitative study was to explore the phenomena of transition, adjustment, and transformation among adult graduate students from India, who made the transition to Nurture University in the southwestern part of the United States. According to Open Doors 2008, since 2001, a majority of the international students in U.S. higher education has been from India. Because of the significant cultural gap between India and the United States, Indian students encounter adjustment difficulties in the host country. To overcome such difficulties, students apply several coping strategies, which in turn lead to a transformational change among them. The transitional adjustment literature on the experiences of the students from India has been very limited. This lack of attention to Indian students, despite the fact that their percentage has been increasing in the U.S. higher education, is an issue of concern and, therefore, calls for research. To achieve this goal, a phenomenological data analysis process presented by Moustakas's modified version of Stevick-Colaizzi-Keen's method was utilized. Data analysis generated the following themes: individual experiences, situational experiences, coping strategies/suggestions, and personal transformation. Under individual experiences, the participants described their experiences in the United States, and differences between their expectations and experiences in relation to Nurture University and general living. Under the situational experiences, study participants described the differences between being a student in the United States versus in India, and the differences between the academic systems of United States and that of India. Further, the application of imaginative variation in step 7 of the data analysis led to the identification of two sub-themes under the theme individual experiences: individual factors that helped in adjustment and individual factors that hindered adjustment in the United States. Sub-themes identified under situational experiences were situational factors that helped in adjustment and situational factors that hindered adjustment in the United States. This study has implications for the home country, host country, adult education, higher education, policy, theory and future research. To ensure the trustworthiness of the data, qualitative procedures such as Epoche, thick descriptions of the phenomenon of transition and member checks, were employed.

Ni-rich NiTi shape memory alloys (SMAs) are capable of attaining a wide range of transformation temperatures depending on the heat treatment conditions and superior thermo-mechanical cycling stability, which are desired for repeated solid-state actuation. High Ni-content Ni-rich SMAs have very low transformation temperatures in a solutionized condition due to the high Ni-content of the matrix. Slow cooling (furnacecooling) from solutionizing temperature and additional aging heat treatments result in the formation of Ni-rich precipitates such as Ni4Ti3, Ni3Ti2 and Ni3Ti and increase transformation temperatures above ambient by depleting excess Ni from the matrix. However, the precipitates do not undergo a martensitic phase transformation and they decrease the transformation strain by reducing the volume fraction of the material capable of transforming. Meanwhile, recent preliminary work shows that Ni3Ti precipitates dominate fatigue failure. The objectives of the present study are: (1) to eliminate Ni3Ti but still have Ni4Ti3 precipitates, which are responsible for the dimensional stability and increase transformation temperatures, (2) to investigate the effect of heat treatments on the transformation strain, and (3) to select single variant Ni4Ti3 precipitates through constrained aging for the formation of oriented internal stress and eventually obtain twoway shame memory effect (TWSME) and enhanced dimensional stability. Based on these objectives, the effect of aging heat treatment on transformation temperatures, microstructural evolution, and shape memory behavior were investigated for a Ni52Ti48 shape memory alloy (SMA) by using differential scanning calorimetry (DSC), optical microscopy, scanning electron microscopy (SEM), and thermo-mechanical testing, including isobaric heating-cooling experiments under various stress levels. It was observed that solutionizing at 900 degree C for 24 hours eliminated Ni3Ti type precipitates, but additional aging heat treatments are needed to form Ni4Ti3 precipitates to increase transformation temperatures. Furnace-cooling and additional aging heat treatment results in the multi-stage martensitic transformation due to chemical and stress inhomogeneities in the microstructure. Aging of the controlled furnace-cooled material at 400 degree C for 48 hours resulted in the highest transformation temperatures among all processing conditions investigated due to the combination of Ni3Ti precipitates and 27 percent volume fraction of the Ni4Ti3 precipitates, which led to the depletion of Ni from the transforming matrix. However, since overaging results in losing coherency of the precipitates, dimensional stability during isobaric thermal cycling was negatively impacted.

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In this thesis, we investigate the transformation bandwidth and the thickness sensitivity of the anisotropic-slab linearly polarizes (LP) to circularly polarized (CP) polarizer. We define a transformation bandwidth and the thickness sensitivity based on the axial ratio. New methods are proposed that can eliminate the lengthy derivation and give deeper physical insight to the problem. Under the small reflection approximation, i.e., only the forward waves are considered, our methods can be applied to the design of the anisotropic-slab LP to CP polarizer. For the single anisotropic slab, the effect is represented graphically on the polarization ratio plane. It is shown that the polarization locus for a given axial ratio leads to a circle in the polarization state diagram. When combined with the graphical description of the change in the polarization state, the transformation bandwidth and the thickness sensitivity from an initial LP wave to a desired CP wave can be obtained easily. Furthermore, we present a method using the equivalent circuits to represent the polarization effect in anisotropic media, so that some concepts of the electric circuit can be applied. This method is more convenient in dealing with the polarization change when multiple anisotropic-slabs exist. The transformation bandwidths and the thickness sensitivities for the anisotropic-slab polarizer for several lossless media are studied. The results are discussed and illustrated.

The traditional manufacturing industry in Taiwan in these few years have been severely challenged by the changing business environment. Under the public opinions that how the traditional industry gets rid of the fate of becoming the declining industry, there are still some companies achieving their success implicitly. To accompany with human resource practices, they create unique competitive advantages and values to overcome the threat by the economic depression and globalization competitiveness. A case study method is used in this thesis. Ten companies in traditional manufacturing industry with superior organizational performance and histories of transformation or related actions for business growth are targeted to explore how the traditional manufacturing industry strengthens or develops different human resource abilities according to different transformation strategies while facing different evolutional opportunities. In this thesis, internal fit of universalistic perspective and external fit of contingent perspective are used to investigate the internal mutual fitness among the human resource practices within the organization respectively. A set of core human resource practices which fit the characteristics of traditional manufacturing industry in Taiwan will be proposed as the core of integrated human resource practices. In addition, from the point of external fit, this thesis also explores the fitness of human resource practices and organizational strategies. To the companies with different transformation strategies, including changing strategic frame, investing resources, changing processes, and solidifying relationships, appropriate human resource practices should also be addressed to strengthen and develop the correspondent dynamic human resource abilities as needed. Therefore, the following propositions are proposed in terms of the inductive inference of interviewing with the ten cases and reviewing the related literature extensively. Propositions 1: The core human resource practices for traditional manufacturing industry in Taiwan are: Focus on employees¡¦ steadiness, hard-working spirits, and employee disciplines while recruiting, high wages, extensive benefits, incentives with cash payment, behavior-oriented and results-oriented performance appraisal, on-the-job training and skill development, promotion from within, harmonious employer-employee relationship, and long-term job security. The more the organization implements those practices, the more the organization could attain competitive advantages and receive superior organizational performance. Propositions 2: In accordance with different transformation and growth anchors, the human resource practices are also different. There are four anchors of transformation strategies including strategic frames, resources, processes, and relationships. Proposition 3: In terms of reengineering strategic frames as the transformation strategy, the organization should emphasize innovative ability while implementing human resource practices. To reverse employees¡¦ value by hard-culture reengineering, the organization could receive knowledge and ability which is different from the one supporting the old strategic frames. Proposition 4: In terms of investing resources as the transformation strategy, the organization should emphasize intensive ability while implementing human resource practices. To intensify and retain the original core techniques, the organization could upgrade the core techniques to the advanced level in order to expand the potential markets. Proposition 5: In terms of changing processes as the transformation strategy, the organization should emphasize participative ability while implementing human resource practices. The organization could accentuate operation efficiency in order to attain the main purposes of reducing cost and improve quality. Proposition 6: In terms of solidifying relationships as the transformation strategy, the organization should emphasize service ability while implementing human resource practices. The organization could draw on the strength of each to offset the weakness of the other among the stakeholders in order to develop competitive advantages.

This thesis is about the phase transformation, shape, size distribution and coalescence of TiO2 (part I) and ZrO2 (part II) nanopartilces produced by Nd-YAG laser ablation on metal targets under oxygen background gas, and characterized by analytical electron microscopy. The optimum laser ablation condition that satisfactory and routinely yield high-pressure phases of TiO2 (i.e. £\-PbO2-type and fluorite-related structures) and ZrO2 with high residual stress were reported. Part I-1 focuses on physical coagulation, by Van der Waals force, of the TiO2 condensates at temperatures up to about 1000 K as a result of post-condensation radiant heating. In part I-2, imperfect oriented attachment of nanoparticles over specific surfaces is rationalized to cause accretion and defects for the rutile condensates. Brownian motion may proceed above a critical temperature for anchorage release at the interface of imperfect attached nanoparticles until an epitaxial relationship is reached. Part I-3 deals with further the Brownian-type rotation of the imperfectly impinged £\-PbO2-type TiO2 and rutile nanocondensates until interfacial-energy cusp was reached. In part I-4 laser ablation condensation synthesis of dense TiO2 polymorphs and their phase transformations were documented. Part II-1 is about dense tetragonal (t)-ZrO2 and cubic (c-) nanocondensates which were synthesized under very rapid heating and cooling by pulsed Nd-YAG laser ablation with oxygen background gas. The t-ZrO2 nanoparticles were found to form deformation twins/faults and followed unique transformation path upon local electron dosage. Electron diffraction indicated that the dense c- and t- phase with specific size and residual stress were allowed to relax and/or kinetically phase change into lower-energy state as constrained by the intersections of the internal energy vs. cell volume plots calculated for the two polymorphs (Part II-2).

This thesis presents a geometry design method to generate the surfaces of the globoidal cam with the conical roller follower. Based on the trace of the rigid body and the theory of differential geometry, the conjugate surfaces can be the offset surfaces of the ruled surface. With different roller¡¦s axial height, its radius and the meshing vector also be changed. For this reason, the contact points on the outward roller are hard to find. To overcome this problem, we propose the triangular graph with meshing angle, it can present the vector quantity caused from the motion angle. We replace it into the procedures of the rigid body transformation method to derive the cam surfaces with the conical roller follower. Furthermore, two models with modified sine and constant velocity motion curves are generated and analyzed.

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Abstract Taiwan Synthetic Resin industry filed, undergoing fifty hard years, this is a mature industry and most of companies have been built up a certain scale of production. Since 1997 the China government combined economic reform with open policy to create a rapid economy growth. With the appeal of market superiority rising and low production cost, truly attracts many inverters enter the target market. Under such strong market competitive, some of Taiwan Synthetic Resin companies have successfully transferred into a high-tech industrial territory, some of companies were standing on their original basis to improve its competition ability. Hence, there is obviously difference of the final business performance in between them. This thesis is based on the case study for Q company, engaged in manufacturing Synthetic Resin related products. The research methodologies take various theoretical analyses such as the ¡§Value Chain¡¨ model of Michael Porter and ¡§Strategic Alliance¡¨ to investigate the business strategy of those listed companies and OTC of Taiwan Synthetic Resin industry. Hope this research should provide useful information about the related strategic usage and future development of the Synthetic Resin industry. The key points of finding in this study may be summarized as under: 1) The technical resource of Taiwan Synthetic Resin industry is mainly demanded on technical alliance and the R&D capability is still under developing. 2) The rapid economic growth and development of the Mainland China caused more difficult environment for Taiwan company future development in the business transformation strategy. 3) The enterprise resource is key success factor in achieving competitive advantages in operation, technology and marketing in the industry field. Key words: Synthetic Resin¡BValue Chain¡BStrategic Alliance¡BBusiness transformation